Rider platform for self-propelled vehicle

ABSTRACT

A self-propelled vehicle comprises a frame and a platform pivotally mountable to a rear portion of the vehicle frame. The platform is pivotally movable between a first position in which the platform extends generally horizontally from the rear portion of the frame to support a rider during operation of the vehicle, and a second position in which the platform is removably secured in a generally upright position-adjacent the rear portion of the frame to enable walk-behind operation of the vehicle.

CROSS-REFERENCE TO RELATED APPLICATION

This patent application claims the benefit of the filing date ofProvisional U.S. Patent Application Ser. No. 60/609,206, entitled “RIDERPLATFORM FOR SELF-PROPELLED VEHICLE,” and having filing date of Sep. 10,2004, which is incorporated herein by reference.

BACKGROUND

Skid steer loaders have become common in construction and materialshandling because of their relatively small size, which lends greatversatility and maneuverability. However, in some instances, even theseskid steer loaders are too large. Accordingly, a smaller version ofthese loaders has been developed, which are generally known asself-propelled utility vehicles as well as walk-behind loaders, compactutility loaders, or mini skid steer loaders. These self-propelledvehicles are narrower, and more nimble, allowing the operator tonegotiate tighter spaces. In these vehicles, instead of the operatorsitting in the vehicle in a seat, the operator walks behind the loaderand guides the loader with hand controls located at a rear of theloader. With the controls, the operator controls movement of the loaderas well as operation of any attachments such as a loader, auger, bucket,etc. These walk-behind loaders also permit quick access and exit fromcontrol of the loader, since the operator need not sit or stand in anenclosure of the loader to operate the loader.

However, since the operator no longer rides on the loader, the operatormay be forced to walk through substances, such as mud, dirt, or othermaterials over which the loader travels. In addition, when moving overuneven terrain or steep terrain, the operator is required to maintainstable footing and exert energy to keep up with the loader. Thissituation can impair the operator's ability to maintain their hands andarms at the controls of the loader, thereby diminishing the function ofthe self-propelled loader. Fatigue caused by this constant walking alsocan further impair hand control of the loader in a walk-behind position.

For these reasons, neither conventional skid-steer loaders norconventional self-propelled utility vehicles meet all the challengesfaced by operators of these vehicles.

SUMMARY

A self-propelled vehicle comprises a frame and a platform pivotallymountable to a rear portion of the vehicle frame. The platform ispivotally movable between a first position in which the platform extendsgenerally horizontally from the rear portion of the frame to support arider during operation of the vehicle, and a second position in whichthe platform is removably secured in a generally upright positionadjacent the rear portion of the frame to enable walk-behind operationof the vehicle.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view schematically illustrating a self-propelledvehicle with a rider platform in an in-use position, according to anembodiment of the present invention.

FIG. 2 is a side view schematically illustrating a self-propelledvehicle with a rider platform in a storage position, according to anembodiment of the present invention.

FIG. 3 is a side view schematically illustrating a self-propelled mowerwith a pivoting rider platform, according to an embodiment of thepresent invention.

FIG. 4 is a perspective view of a self-propelled vehicle with a riderplatform in a storage position, according to an embodiment of thepresent invention.

FIG. 5 is partial side view of a self-propelled vehicle with the riderplatform in an in-use position, according to an embodiment of thepresent invention.

FIG. 6 is partial side view of the embodiment of FIG. 5 with the riderplatform in an intermediate position, according to an embodiment of thepresent invention.

FIG. 7 is partial side view of the embodiment of FIG. 5 with the riderplatform in a storage position, according to an embodiment of thepresent invention.

FIG. 8 is enlarged perspective view of a pivot mechanism and stopmechanism of a platform system, according to an embodiment of thepresent invention.

FIG. 9 is an enlarged perspective view of a pivot mechanism and variablypositionable stop mechanism of a platform system, according to anotherembodiment of the present invention.

FIG. 10 is schematic illustration of the variably positionable stopmechanism of the embodiment of FIG. 9, according to an embodiment of thepresent invention.

FIG. 11 is a side view of a platform system with an alternative mountingframe, according to an embodiment of the present invention.

FIG. 12 is a side view of a rider platform in an in-use position,according to another embodiment of the present invention.

FIG. 13 is an enlarged perspective view of a pivot mechanism and a stopmechanism of the embodiment of FIG. 12, according to an embodiment ofthe present invention.

FIG. 14 is a side view of the embodiment of FIG. 12 with the riderplatform in an intermediate position, according to an embodiment of thepresent invention.

FIG. 15 is a side view of the rider platform of the embodiment of FIG.12 in a storage position, according to an embodiment of the presentinvention.

FIG. 16 is a side view of the rider platform of the embodiment of FIG.12 in an in-use position with an alternative mounting frame, accordingto an embodiment of the present invention.

FIG. 17 is a perspective view of a platform system, according to anotherembodiment of the present invention.

DETAILED DESCRIPTION

In the following detailed description, references made to theaccompanying drawings, which form a part hereof, and which isillustrated by way of illustrations specific embodiments in which theinvention may be practiced. In this regard, directional terminology,such as “front,” “back,” etc., is used with reference to the orientationof the figures(s) being described. Because components of embodiments ofthe present invention can be positioned in a number of differentorientations, the directional terminology is used for purposes ofillustration and is in no way limiting. It is to be understood thatother embodiments may be utilized and structural or logical changes maybe made without departing from the scope of the present invention. Thefollowing detailed description, therefore, is not to be taken in alimiting sense, and the scope of the present invention is defined by theappended claims.

Embodiments of the invention enable convertible use of self-propelledvehicles, such as mini skid steer loaders or compact utility loaders, ina walk-behind mode or in a ride-on-platform mode.

FIG. 1 is a side view schematically illustrating a self-propelledvehicle 10, according to an embodiment of the present invention. Asshown in FIG. 1, self-propelled vehicle 10 comprises vehicle frame 12including front portion 13, rear portion 14, mover 15, and controls 16.In one embodiment, a tool 18 is removably attached to front portion 13of vehicle frame 12. Mover 15 comprises powered wheels or tracks formoving vehicle 10 across ground G.

A platform 20 is mounted to rear portion 14 of vehicle frame 14 viapivot mechanism 22. Platform 20 defines an elevated operator zone 23 atrear portion 14 of vehicle 10 for operating controls 16. In the in-useposition shown in FIG. 1, the operator can ride on the platform 20 abovethe ground (shown by distance H1) while operating the controls 16 ofvehicle 10.

FIG. 2 is a side view of the embodiment of FIG. 1, except showingplatform 20 in a storage position. In the storage position, platform 20is pivoted via pivot mechanism 22 into a generally upright position andsecured into close proximity to the rear portion 14 of the vehicle 10 toenable walk-behind use of vehicle 10. In the storage position, platform20 enables unobstructed pedestrian operation of the self-propelledvehicle 10 in the walk-behind mode.

This pivotally mounted platform 20 can be constructed as a permanentfeature of the self-propelled vehicle 10 or as retro-fit feature that isattached to a self-propelled vehicle not having a rider platform.

Riding on the platform 20 introduces greater feedback between movementof the vehicle/loader relative to the operator, since the platform 20enables an operator to sense vehicle movement through their legs andfeet, as well as through their hands at the controls 16. In addition,platform 20 places the operator at a greater height relative to thevehicle 10, enabling better line-of-sight to tool 18 (e.g., a loaderbucket, auger, pallet fork, etc) at front portion 13 to enhance operatorcontrol of tool 18 and/or vehicle 10. Providing a ride-on platform 20also enables the operator greater vision of the terrain to spotobstacles, people, and any objects to be manipulated by the vehicle 10.The operator also experiences less fatigue when riding on platform 20than in a walk-behind mode since they are carried by the vehicle 10.Accordingly, many aspects of operating a self-propelled vehicle 10 areenhanced via the elevated operator zone 23 created by the rider platform20.

Providing a ride-on platform 20 also enables the weight of the operatorstanding on the platform 20 to act as an additional counterweight on aself-propelled vehicle 10, thereby increasing the effectiveweight-bearing capacity of the vehicle at the front portion 13 of thevehicle frame 12. The weight of the operator also contributes to thefunction of the platform 20 as an anti-tipping measure, thereby limitingthe extent of rearward rotation of vehicle 10. In particular, theadditional effect of the long moment arm relative to a gravitationalcenter of the vehicle (i.e., a fulcrum about which the front and rear ofthe vehicle tip relative to one another) that is provided by theoperator standing on platform 20 multiplies the effect of theoperator-provided counter-weight. Moreover, since the operator is notharnessed to a seat, the operator can quickly hop-on or hop-off theplatform 20 to quickly add or subtract the counter weight. For example,the lifting capacity at the front portion 13 of the vehicle 10 can beincreased when the self-propelled vehicle 10 is on a level surface (or adeclining surface) by the operator hopping on the platform 20 at therear portion 14 of the vehicle 10 to add a counter weight. In anotherexample, when the vehicle 10 is on an inclining surface, and the frontportion 13 of the vehicle is not carrying a load, then the operator canhop off the platform 20 to limit the extent of backward tipping of thevehicle.

Providing a ride-on platform 20 also enhances tipping control of thevehicle by providing a structure capable of striking the ground, therebylimiting backward rotation of the vehicle 10 when the vehicleexperiences loads or terrain that would otherwise cause the frontportion 13 of the vehicle to rise in elevation significantly relative tothe rear portion 14 of the vehicle. In one embodiment, rollers areattached to the vehicle frame (via a mounting frame of the platform)adjacent the rear portion 14 of the vehicle 10 to act an additionalanti-tipping measure.

In one embodiment, pivot mechanism 22 also comprises a latch mechanism.The pivot mechanism 22 supports pivotal movement of the platform 20relative to the rear portion 14 of the vehicle frame 12 between agenerally horizontal in-use position (FIG. 1) and a generally uprightstorage position (FIG. 2). In one aspect, in the storage position of theplatform, the latch mechanism is engaged to releasably secure platform20 relative to rear portion 14 of the frame 12 to maintain platform 20in a generally upright position, thereby enabling walk-behind use. Inthe in-use position, the latch mechanism is disengaged to releaseplatform 20 relative to rear portion 14 of the frame 12, therebyallowing platform 20 to pivot downward to rest in a generally horizontalin-use position to receive a rider. To return the platform 20 to thestorage position (FIG. 2), the platform 20 is pivotally rotated upwardvia pivot mechanism 22 toward the frame 12 until the latching mechanismis engaged to releasably secure the platform 20 relative to rear portion14 of the frame 12.

Additional components and/or alternative components also comprise otherembodiments of the invention. In one embodiment, the platform 20 isheight-adjustable in the in-use position enabling the rider to bepositioned at different heights relative to the controls 16 mounted atthe rear portion 14 of the self-propelled vehicle 10. In anotherembodiment, a shock-absorbing connecting link is interposed between theplatform 20 and the vehicle frame 12 to absorb the machine vibration tothe operator when the platform 20 is in the riding in-use position,thereby minimizing operator fatigue. In another embodiment, the platform20 includes a padded portion at its rear end and/or its sides to protectan operator or to protect nearby equipment and surroundings from contactwith edges or corners of the platform. The padded portion comprises oneor more layers or coatings of plastic, rubber, foam, or other cushioningmaterials. The padded portion also can comprise a non-slip surface.

Embodiments of the present invention also comprise variations onmechanisms for pivotally attaching a rider platform to a self-propelledvehicle. In one embodiment, platform 20 is mounted with two pivotmechanisms, with the pivot mechanisms located on opposite sides of theplatform 20. In another embodiment, the pivot mechanism is locatedadjacent a central region of the platform between two opposite sides ofthe platform. In this embodiment, a single link pivotally connects theplatform 20 to a rear portion 14 of the frame of the self-propelledvehicle 10 and includes a locking mechanism to enable securing theplatform in either a generally horizontal in-use position or a generallyupright storage position and to enable pivotal movement of the platformbetween the in-use and the storage position.

In one embodiment, the pivot mechanism and its associated latchmechanism are located adjacent each other at a side portion of theplatform. In other embodiments, the pivot mechanism and its associatedlatch mechanism are located in separate positions from each other. Inone aspect, one or more pivot mechanisms are located adjacent a sideportion of the platform while one or more latch mechanisms are locatedadjacent a center portion of the platform. In another aspect, one ormore pivot mechanisms are located adjacent a central portion of theplatform while one or more latch mechanisms are located adjacent a sideportion of the platform.

Embodiments of the invention enable a walk-behind use of the vehicle 10without complete removal of platform 20 from vehicle 10 because of thelow-profile of platform 20 in its storage position. Accordingly, in oneembodiment, platform 20 supports an operator without any additionalwheels or rollers mounted at an outer end of platform or underneathplatform 20. However, in other embodiments, wheels, rollers, or skidsare mountable at an outer end or bottom surface of platform 20 whilestill maintaining a low-profile of platform 20 in its storage position.

FIG. 3 is a side view illustrating a self-propelled landscaping vehicle25, such as a mower. As shown in FIG. 3, vehicle 25 comprises frame 26,handle 27, and controls 28. Vehicle 25 also comprises platform 20 whichis movable via pivot mechanism 22 between an in-use position 20B and astorage position 20A. Platform 20 and pivot mechanism 22 of FIG. 3comprise substantially the same features and attributes as platform 20and pivot mechanism 22 of FIGS. 1-2, except for the replacement ofvehicle 10 with vehicle 25.

These embodiments of the invention, and additional embodiments of theinvention, are described in greater detail in association with FIGS.4-17.

FIG. 4 is a perspective view of a platform system 40 of a self-propelledvehicle 30, according to an embodiment of the invention, including arider platform 41 in a storage position. FIGS. 5-7 are side views of theplatform system 40 of FIG. 4 showing the rider platform in an in-useposition, an intermediate position, and a storage position,respectively, according to one embodiment of the invention. Variousaspects and functions of platform system 40 are described together inassociation with FIGS. 4-7, which illustrate the same components indifferent views.

As shown in FIG. 4, vehicle 30 includes vehicle frame 31, mover 32,lower portion 33, rear portion 34 having rear surface 35 and a frontportion substantially similar to front portion 13 in FIG. 1. The frontportion enables removably securing various attachments such as loaderbuckets, pallet forks, augers, mowers, etc. Mover 32 comprises a drivemechanism such as power-driven wheels, tracks, etc. Vehicle 30 alsoincludes control module 38 positioned at rear portion 34. Platformsystem 40 is removably attachable to vehicle frame 31, and onceattached, enables pivotal movement of platform 41 between an in-useposition (shown in FIG. 5) and a storage position (shown later in FIG.7). In the in-use position, platform system 40 enables ride-on operationof vehicle 30. In the storage position, platform system 40 enableswalk-behind operation of vehicle 30.

Platform system 40 defines platform 41 and is mounted to vehicle frame31 via mounting bracket 42. Platform 41 is sized and shaped to supportan operator standing upright, with some ability to maneuver their feeton the platform. As shown in FIG. 4, platform 41 is a generallyrectangular shaped member. Platform 41 comprises inner end 50, outer end52, first side 54, second side 56, upper support surface 58 (FIG. 5),and lower surface 59. Platform system 40 includes, for mounting on eachof the opposite sides 54,56 of platform 41, a pivot mechanism 44 andlatch mechanism 46, as well as a mounting frame 42 to connect platform41 to vehicle frame 31. The respective pairs of pivot mechanisms 44,latch mechanisms 46, and mounting frames 42 are laterally spaced apartat the rear portion 34 of vehicle by a distance generally correspondingto a width of rear portion 34. In another embodiment, the structure andfunction of mounting frame 42 is provided by vehicle frame 31 so thatpivot mechanism 44 and latching mechanism 46 are directly coupled fromplatform 41 to vehicle frame 31 without a mounting frame 42.

Self-propelled vehicle 30 including platform system 40 is described andillustrated in greater detail in association with FIGS. 4-17.

As shown in FIGS. 4-7, mounting frame 42 is sized and shaped to enablepivot point 80 of pivot mechanism 44 to be located as close as possibleto vehicle frame 31 with enough clearance for inner end 50 of platform41 to rotate relative to rear surface 35 of vehicle frame 31 and forsupport surface 58 of platform 41 to be closely adjacent rear surface 35of vehicle frame 31, when platform 41 is in its storage position. In oneaspect, as shown in FIGS. 4-5, mounting frame 42 includes first portion70 and second portion 71. First portion 70 of mounting frame 42 isfastened to rear surface 35 of vehicle frame 31 and second portion 71extends outwardly from first portion 70 at an angle (e.g., 90 degrees)to enable mounting of pivot mechanism 44, latch mechanism 46, roller 90and any other associated components of attachable platform 40 relativeto mounting frame 42.

FIG. 4 also reveals aspects of pivot mechanism 44, including but notlimited to, pivot arm 60, pivot point 80, and stop mechanism 94. Asshown in FIG. 4, pivot arm 60 includes first portion 62 and secondportion 64 forming a generally obtuse angle relative to each other atjunction 66. First portion 62 of each pivot arm 60 is mounted to arespective first and second side (54, 56) of platform 41. Second portion64 of each pivot arm 60 is pivotally mounted (at pivot point 80) to arespective mounting frame 42 on opposite sides of rear surface 26. Pivotpoint 80 is a point on mounting frame 42 about which pivot arm 60 ofplatform 41 pivots to move platform 41 between the in-use position (FIG.5) and the storage position (FIGS. 4,7). Pivot point 80 comprises acombination of pin(s), hole(s), and fastener(s) adapted to enable secondportion 64 of arm 60 to pivot relative to second portion 71 of mountingframe 42.

In one aspect, the length of first portion 62 and second portion 64 ofpivot arm 60, relative to each other, and the angle formed between firstportion 62 and second portion 64 are selected so that when platform 41is pivotally mounted to vehicle frame 31 via pivot arm 60, pivot arm 60enables extension of platform 41 in a generally horizontal restingposition relative to the vehicle frame 31, and also permit adequateclearance for pivoting of inner end 50 of platform 41 relative tovehicle frame 31 to move platform 41 to its storage position (FIGS. 4and 7). A variety of lengths of first portion 62 and second portion 64and a variety of angles at junction 66 of pivot arm 60 can be used toachieve pivoting function depending upon the size and the geometry ofvehicle frame 31. Accordingly, pivot arm 60 is not strictly limited tothe shape and geometry shown in FIGS. 4-17.

As shown in FIGS. 4-5, stop mechanism 94 is secured to mounting frame42, via spring-loaded fastener 96, generally below pivot point 80 tolimit pivoting movement of arm 60. Stop mechanism 94 is furtherdescribed in association with FIGS. 5-17.

FIGS. 4-7 also illustrate latch mechanism 46. Latch mechanism 46selectively maintains platform 41 in the either storage position or thein-use position. As shown in FIG. 5, latch mechanism 46 comprises body47, pivot point 82, first end 85, beveled surface 86, second end 87,recess 88, and flat surface 89. Pivot point 82 comprises a point oflatch body 47 that is pivotally mounted relative to a portion ofplatform 41, or a pivot arm 60 of platform 41 (best seen in FIG. 4).Pivot point 82 comprises a combination of pin(s) and hole(s) enablingpivotal movement of latch body 47 adjacent first end 85 so that secondend 87 swings in and out of releasable engagement with pin 84 ofmounting frame 42. As shown in FIG. 5, in the in-use position in whichplatform 41 rests in a generally horizontal position, gravitationalforces cause beveled surface 86 of latch body 47 to rest against pin 84of mounting frame 42.

FIGS. 4-7 also illustrate roller 90, which is mounted to a lower portionof mounting frame 42 in one embodiment of the invention. In one aspect,roller 90 is positioned to make first contact with the ground in theevent that vehicle 30 tips backward during ordinary use, therebyrelieving pivot mechanism 44 and platform 41 from wear and tear due toground contact, and helping to stabilize the rider on platform 41.Accordingly, roller 90 acts as a balancing mechanism for both the rider(standing in operator zone 23 of FIG. 1) and the vehicle 30 whenmaneuvering the vehicle 30 over an obstacle, uneven terrain, or steepterrain. As shown in FIG. 5, the bottom of roller 90 is positioned at aheight H2 above the ground G at a height lower than the generaloperating height H1, at which a lower surface 59 of platform 41generally extends above ground G. Accordingly, roller 90 is in positionto generally strike the ground before platform 41 during a rearwardtipping of vehicle frame 12.

In another embodiment, roller 90 is omitted from platform system 40.

While not shown in each Figure of FIGS. 4-17, it is understood thatplatform 40 of vehicle 30 comprises roller 90 in each embodiment, exceptwhere roller 90 is omitted selectively as desired by an operator,retailer, manufacturer, etc. In addition, a roller 90 is generallymounted on both sides of the platform (e.g. opposite sides of platform41 at a respective mounting frame 42 as shown in FIGS. 4-5).

FIG. 6 is a side view of platform 40 in an intermediate position, duringpivoting movement (represented by directional arrow A) between thegenerally horizontal in-use position (FIG. 5) and the generally uprightstorage position (FIG. 7), according to one embodiment of the invention.For discussion purposes, platform 41 is assumed to be moved upward fromthe in-use position toward the storage position. As shown in FIG. 6,outer end 52 of platform 41 is lifted upward with inner end 50 ofplatform 41 pivoting relative to pivot point 80, thereby causing beveledsurface 86 of latch body 47 to slide upward against fixed pin 84 onmounting frame 42. This sliding motion continues as outer end 82 ofplatform 41 is pivotally raised upward so that flat surface 89 of latchbody 47 begins to slide against pin 84. As shown in FIG. 6, whenplatform 41 becomes generally upright and generally parallel to rearsurface 26 of vehicle frame 12, recess 88 of latch body 47 drops (byforce of gravity) onto pin 84. In this position, the operator releasesouter end 52 of platform 41 allowing gravity to exert downward forcesagainst second end 52 of platform 41, with recess 88 of latch body 47maintaining pressing engagement with pin 84 of mounting frame to preventdownward pivotal movement of platform 41.

FIG. 7 is a side view illustrating platform 41 in a generally uprightstorage position, according to one embodiment of the invention. As shownin FIG. 7, with recess 88 of latch body 47 resting securely on pin 84 ofmounting frame 42, platform 41 is securely positioned close to rearsurface 35 of vehicle frame 31 with support surface 58 spaced a shortdistance D from rear surface 35. The distance D can be selected toeither larger or smaller than shown, and support surface 58 optionallyneed not be generally parallel to rear surface 35 of vehicle frame 31.

To restore platform 41 to its in-use position, the operator simplysupports outer end 52 of platform 41 while lifting second end 87 oflatch body 47 upward to withdraw recess 88 from its locked position onpin 84. As platform 41 is rotated downward to the in-use position, flatsurface 89 and beveled surface 86 of latch body 47 slide against pin 84(shown in FIG. 6) until platform 41, including latch mechanism 46, arereturned to their in-use position (FIG. 5).

In one embodiment, pivot mechanism 44 and latch mechanism 46 are securedrelative to platform 41 independent of each other. In anotherembodiment, pivot mechanism 44 and latch mechanism 46 can take severalforms, in addition to those shown, including components such asfasteners, hooks, pivot members, pins, or holes, that reciprocallyengage each other and that can be mounted on either the frame of thevehicle and/or the platform in various combinations to achieve thepivoting and latching functions described in association with FIGS.1-17.

FIG. 8 is enlarged perspective view of platform 41 in its in-useposition, further illustrating interaction between pivot mechanism 44and stop mechanism 94. As shown in FIG. 8, second portion 64 of pivotarm 60 extends outwardly from underneath inner end 50 of platform 41 andup to pivot point 80. Contact surface 65 of second portion 64 restsagainst contact surface 95 of stop mechanism 94. Stop mechanism 94prevents further pivotal movement of arm 60 relative to pivot point 80,thereby maintaining the position of platform 41 in a generallyhorizontal in-use position because of the relative angle of secondportion 64 and first portion 62 of arm 60. Fastener 96 includes spring97 and maintains stop mechanism 94 in position relative to mountingframe 42. As shown in FIG. 8, stop mechanism 94 is a generally discshaped member.

In one embodiment, stop mechanism 94 is made from a hard material, suchas a metal. In another embodiment, stop mechanism 94 is made from agenerally elastic polymer material to thereby act as a shock-absorbinglink between platform 41 and vehicle frame 31. This shock-absorbing linkintroduces a dampening effect between platform 41 and vehicle frame 31,thereby diminishing the amount of shock, dramatic forces, and/orvibrations transmitted from vehicle frame 31 to an operator on platform41.

Moreover, this shock-absorbing link is not strictly limited to providingstop mechanism 94 as an elastomeric material, but can extend to othertypes of dampening materials, as well as other dampening and/or springmechanisms and/or other suspension mechanisms, that are interposedbetween platform 41 and vehicle frame 31. The shock-absorbing parametersof this link, including a dampening parameter and spring rate, can beselected to vary the quantity and quality of the shock-absorbing link,including making a spring-based shock-absorbing link, either damped orundamped.

This shock-absorbing link can be independent of pivot mechanism 44 andstop mechanism 94, or can be a component of pivot mechanism 44 and/orstop mechanism 94.

A shock-absorbing link, according to one embodiment of the invention, islater described in association with FIG. 17.

FIG. 9 is an enlarged perspective view of platform 40 in its in-useposition, illustrating another embodiment including a stop mechanism 100(in place of stop mechanism 94) which enable platform 41 to be adjustedto different heights relative to vehicle frame 31 in the in-use positionof platform 41. As shown in FIGS. 9-10, stop mechanism 100 includes agenerally rectangular-shaped block having mounting hole 101, and fourcontact surfaces 102, 104, 106, and 108. As shown in FIG. 9, contactsurface 102 of block 100 is positioned to receive pressing engagementfrom contact surface 65 of arm 60. However, fastener 96 enablesselective rotation of block 100 into four different positions so thateach of the other contact surfaces 104, 106 and 108 of block 100 can bepressingly engage contact surface 65 of pivot arm 60.

FIG. 10 is a schematic drawing, illustrating block 100 with its contactsurfaces 102-108 and mounting hole 101. As shown in FIG. 10, mountinghole 101 is positioned off-center relative to both a major axis and aminor axis of block 100. This off-center positioning, in combinationwith the rectangular shape of block 100, results in each contact surface102-108 causing contact surface 65 of pivot arm 60 to be supported at adifferent distance relative to fastener 96 on mounting frame 42, therebycausing platform 41 to be fixed at a different height relative to theground for each of the different contact surfaces 102-108. While FIGS.9-10 illustrate a generally rectangular-shaped block as stop mechanism100, other shaped stop mechanisms (e.g., n-gon, triangular, etc) can beused to achieve desired variable height positioning of platform 41.

FIG. 11 is a side view illustrating a self-propelled vehicle having aplatform 41 (including pivot mechanism 44 and latch mechanism 46) havingsubstantially the same features and attributes as vehicle 30, exceptreplacing mounting frame 42 with mounting frame 150 to accommodate adifferent shape of vehicle frame 160 (similar to vehicle frame 31). Asshown in FIG. 11, pivot mechanism 44 and latch mechanism 46 are mountedto mounting frame 150. Mounting frame 150 is fixed to a side surface 164of vehicle frame 160 in contrast to mounting frame 42 which is fixed torear surface 35 of vehicle frame 31 via portion 70 (FIGS. 4-7).

As shown in FIG. 11, mounting frame 150 comprises first body portion154, holes 152 for mounting to vehicle frame 160, and second bodyportion 158. An imaginary line 156 generally denotes a boundary betweenfirst and second body portions 154, 158. First body portion 154 ofmounting frame 150 is sized and shaped so that when fixed to a sidesurface 164 at the rear portion of vehicle frame 160, boundary 215generally corresponds to a location of rear surface 162 of vehicle frame160 (similar to rear surface 35 of vehicle frame 31) from which secondbody portion 158 extends. This arrangement enables mounting andfunctioning of pivot mechanism 44 and latch mechanism 46 at a pivotpoint 80 and fasteners 84, 96 in a position close to, but spaced from,rear surface 35 of vehicle frame 160 to achieve the functions andfeatures previously described for platform 40 in association withmounting frame 42 (FIGS. 1-10).

Except for the different position of side-mounting frame 150 relative tovehicle frame 160 in FIG. 11 (as compared to the position of mountingframe 42 relative to vehicle frame 31 in FIGS. 4-7), all other featuresand attributes of platform system 40, including platform 41, pivotmechanism 44, and latch mechanism 46 of platform system 200 asillustrated in FIG. 11 are substantially the same as previouslydescribed in association with FIGS. 1-10.

FIG. 12 is a side view illustrating a platform system 200, according toanother embodiment of the invention. As shown in FIG. 12, platformsystem 200 comprises platform 202, pivot mechanism 204, and mountingframe 206. Platform 202 includes support plate 211 and comprises innerend 217 and outer end 218. Support arm 212 comprises outer end 230,secured to and supporting support plate 211, and inner end portion 232which are joined together at junction 235 defining an generally obtuseangle between outer portion 230 and inner end portion 232. Mountingframe 206 comprises first portion 207, second portion 208, and lowerportion 210 defining slot 209. Pivot mechanism 204 comprises componentsmounted on, or interacting with either platform 202 or mounting frame206 to enable pivotal movement of platform 202 between in in-useposition shown in FIG. 12 and a storage position shown later in FIG. 15.

As shown in FIG. 12, pivot mechanism 204 comprises pin 242 mounted onlower portion 210 of mounting frame 206 and slot 234 of inner endportion 232 of support arm 212. In one aspect, pivot mechanism 204 alsocomprises a securing mechanism comprising pin 214 mounted on support arm212 and a slot 209 of lower portion 210 of mounting frame 206. Slot 234of support arm 212 is generally elongate slot with closed ends, enablingsliding movement of inner end portion 232 of support arm 212 relative topin 242. However, pin 214 which protrudes from support arm 212 isadjacent an outer edge 238 of lower portion 210 of mounting frame 206.In one aspect, pin 214 acts to prevent sliding movement of support arm212 (and platform plate 211) inward toward rear surface 35 of thevehicle frame. Further interaction of the components of pivot mechanism204 is described in association with FIGS. 13-16.

As shown in FIG. 12, stop mechanism 250 (shown in phantom) is secured tolower portion 210 of mounting frame 206 and limits movement of inner endportion 232 of support arm 212 via contact at surface 240 of support arm212. Stop mechanism 250 comprises substantially the same features andattributes as stop mechanism 94, as previously described in associationwith FIGS. 1-11, and as further illustrated in FIG. 13.

FIG. 13 is a perspective view of the embodiment of FIG. 12, whichfurther illustrates the components of platform system 200 as describedand illustrated in FIG. 12. As shown in FIG. 13, pin 242 protrudesthrough slot 234 of inner end portion 232 of arm 230 while pin 214protrudes outwardly in a generally opposite direction to enableengagement with slot 209.

FIG. 14 is a side view of the embodiment of FIGS. 12 and 13, accordingto one embodiment of the invention, illustrating the platform 202 in anintermediate position between an in-use position (FIG. 12) and a storageposition (FIG. 15). As shown in FIG. 14, platform 202 is rotated upwardfrom its in-use position (FIG. 12) via rotatable motion of slot 234about pin 242, with pin 214 sliding along (or adjacent to) outer edge238 of lower mounting portion 210, until pin 214 is positioned adjacenta mouth of slot 209. In this position, platform 202 is in a generallyupright position. In one aspect, platform 202 is generally parallel torear surface 35 of the vehicle frame, while in other aspects, thegenerally upright position is not exclusively limited to this generallyparallel relation to rear surface 35 of the vehicle frame.

FIG. 15 is a side view of the embodiment of FIGS. 12-14, according toone embodiment of the invention, illustrating the platform 202 in astorage position. As shown in FIG. 15, platform 202 is moved inward withpin 214 of arm support 212 sliding into slot 209 of lower mountingportion 210, and with slot 234 of inner end portion 232 of arm support212 sliding relative to pin 242. At the completion of this motion, pin214 in slot 209 releasably secures platform in position adjacent to rearsurface 35 of vehicle frame 31 with slot 234 and pin 242 providing anadditional mechanism to maintain the position of platform 202.Accordingly, two simultaneous pin-in-slot movements of pin 214 and slot209, and of pin 242 in slot 234, occur to secure platform 202 relativeto rear surface 35 of the vehicle frame.

At any time desired by the operator, the platform is returned to thein-use position by pulling outer end 218 of platform 202 outward toslidably remove pin 214 from slot 209, with slot 234 of inner endportion 232 sliding relative to pin 242, until pin 214 exits slot 209.In this position, platform 202 is free to rotate downward to the in-useposition shown in FIGS. 12-13, in which stop mechanism 250 supportsinner end portion 232 of arm 212 at surface 240, and pin 214 limitsinward/outward motion of platform 202 relative to the rear surface 35 ofthe vehicle frame.

In one aspect, in both the in-use position and the storage position, thesecuring pin 214 and latching slot 209 are laterally spaced further awayfrom the rear surface 35 of the vehicle frame 31 relative to the pivotpin 242. In another aspect, in the in-use position, the securing pin 214is positioned lower than the pivot pin 242, by virtue of angled innerend portion 232 of support arm 212, and in the storage position, thesecuring pin 214 is positioned vertically above the pivot pin 242.

This arrangement enables movement of only a single platform assembly(including platform 202, arm 212 including slot 234, and pin 214),relative to a mounting frame (including slot 209 and pin 242). In use,the first slot 234 remains both slidably and pivotally engaged to thesecond pin 242 while the first pin 214 is releasably slidable into thesecond slot 209 upon rotation of the entire platform 202. According, theplatform assembly itself effectively acts as the only moving part toenable pivotal movement of platform 202 between the in-use and thestorage position and to enable securing the platform 202 in the storageposition.

In one aspect, platform system 200 uses the force of gravity to maintainthe position of the platform 202. In the storage position, since thesecuring pin 214 and receiving slot 209 are above the pivot pin 242, andslot 209 is angled parallel to rear surface 35, once pin 214 is alignedwithin slot 209, gravity assists a user in pushing pin 214 into slot 209and in maintaining pin 214 in slot 209. When released from the storageposition by pulling platform 202 outward to remove pin 214 from slot209, gravity tends to cause platform 202 rotate downward relative topivot pin 242, with stop mechanism 250 preventing any further movementof platform 202. Accordingly, the arrangement of pins and slots ofplatform system 200 enables the natural force of gravity to facilitatepositioning of platform 202 in its respective storage and in-usepositions.

FIG. 16 is a side view illustrating a platform system 260 for aself-propelled vehicle (including platform 202 and pivot mechanism 204)having substantially the same features and attributes as platform system200 of FIGS. 12-15, except replacing mounting frame 206 with mountingframe 270 to accommodate a different shape of vehicle frame. As shown inFIG. 15, pivot mechanism 204 is mounted to mounting frame 270. Mountingframe 270 is fixed to a side surface of a vehicle frame in contrast tomounting frame 206 which is fixed to rear surface 35 of vehicle frame 31(FIG. 12-15).

As shown in FIG. 16, mounting frame 270 comprises first body portion274, holes 272 for mounting to vehicle frame 31, second body portion276, and slot 278 (like slot 209 in FIG. 12-15). First body portion 274of mounting frame 270 is sized and shaped so that when fixed to a sidesurface adjacent rear surface 35 of a vehicle frame, pivot mechanism 204is in a position close to, but spaced from, rear surface 35 of thevehicle frame to achieve the functions and features previously describedfor platform 202 in association with mounting frame 206 (FIGS. 12-15).

FIG. 17 is a perspective view illustrating a platform system 300,according to an embodiment of the invention. Platform system 300comprises substantially the same features and attributes as platformsystems (including a pivot mechanism and latch mechanism) described inassociation with FIGS. 1-16, except additionally including ashock-absorbing member 310 as shown in FIG. 17. Shock-absorbing member310 establishes a link between platform 202 and rear surface 35 ofvehicle frame 31 to minimize vibration that would otherwise betransmitted to an operator standing on platform. In one aspect, theshock absorbing link is a piston-cylinder arrangement (as shown) whichprovides a variable length to member 310 to facilitate pivotal movementof platform 202. In another aspect, the shock absorbing link is anelastomeric member. In other aspects, the shock absorbing link is aspring member or other dampening mechanism.

In addition, each end of member 310 is pivotally mounted relative toplatform 202 and relative to rear surface 35 to enable pivoting ofplatform 202 between the previously described and illustrated in-use andstorage positions of platform 202.

In another embodiment, platform system 300 omits a pivot mechanism (suchas pivot mechanism 44) and a latch mechanism (such as latch mechanism46) and relies solely on member 310 to provide a pivoting function forplatform 202 and a latching function (via gas pressurization in acylinder of member 310).

In one aspect, member 310 is mounted at a side of platform 202 as shownin FIG. 117 while in other aspects, member 310 is mounted adjacent acentral region of platform between opposite sides of platform 202.

Embodiments of the present invention enable convertible use ofself-propelled vehicles in either a walk-behind or ride-on-platform modeby simple pivotal movement of a platform between a generally horizontalposition for riding operation and a generally upright, selectivelyengaged storage position for walk-behind operation. In one aspect, apivot mechanism enables single hand use to simply flip the platformupward for storage and to flip the platform down for use. The platformcan be built as part of the vehicle frame or attached later as aretro-fit assembly.

Although specific embodiments have been illustrated and described hereinfor purposes of description of the preferred embodiment, it will beappreciated by those of ordinary skill in the art that a wide variety ofalternate and/or equivalent implementations may be substituted for thespecific embodiments illustrated and described without departing fromthe scope of the present invention. Those with skill in the mechanical,electromechanical, electrical, and computer arts will readily appreciatethat the present invention may be implemented in a very wide variety ofembodiments. This application is intended to cover any adaptations orvariations of the preferred embodiments discussed herein. Therefore, itis manifestly intended that this invention be limited only by the claimsand the equivalents thereof.

1. A self-propelled vehicle comprising: a frame; a rider supportassembly including at least one support element and a platform extendinggenerally outward from the at least one support element, wherein the atleast one support element is pivotally mounted, via a pivot mechanism,relative to a rear portion of the vehicle frame, the at least onesupport element is pivotally movable between a first position in whichthe platform extends in a generally horizontally orientation from therear portion of the frame and is spaced above a ground surface tosupport a rider standing in an elevated position during ride-onoperation of the vehicle and a second position in which the at least onesupport element is in a generally upright position adjacent the rearportion of the frame to enable walk-behind operation of the vehicle,wherein the at least one support element is interposed between the pivotmechanism and the platform to cause the platform to be spaced apart fromthe pivot mechanism; a stop mechanism located at the rear portion of thevehicle and configured to releasably engage the at least one supportelement to prevent pivotal movement of the platform downward beyond thegenerally horizontal orientation of the first position of the platform,wherein the stop mechanism is independent and separate from theplatform, and wherein the stop mechanism is separate and independent ofthe pivot mechanism; and a latch mechanism disposed on the at least onesupport element of the rider support assembly, the latch mechanismconfigured to be automatically releasably engaged at the rear portion ofthe vehicle frame via an at least one-handed, first manipulation of theplatform to releasably secure the platform in the second position andthe latch mechanism configured to be automatically disengaged via an atleast one-handed, second manipulation of the platform to release theplatform from the second position for movement into the first position.2. The vehicle of claim 1 wherein the latch mechanism comprises: a hookmember pivotally mounted on the at least one support element of therider support assembly and positioned between the pivot mechanism andthe platform, the hook member including a recess; and a securing memberdisposed at the rear portion of the frame in a location to enable therecess of the hook member to be disengaged from the securing member whenthe platform is in the first position and to enable the securing memberto releasably receive and secure the recess of the hook member when theplatform is moved into the second position.
 3. The vehicle of claim 1wherein the stop mechanism is made from an elastomeric materialconfigured to absorb shock between the platform and the frame of thevehicle.
 4. The vehicle of claim 1 wherein the stop mechanism is agenerally rectangular-shaped block rotatably positionable into at leasttwo positions, in which each respective position causes a differentsurface of the block to support the at least one support element of therider support assembly, and wherein each respective different surface ofthe block extends at a different angle relative to the frame to causethe support to be at a different height relative to the frame to therebyposition the operator on the platform at different heights relative tothe frame.
 5. The vehicle of claim 1 wherein the platform furthercomprises a vibration-absorbing link interposed between the platform andthe frame.
 6. The vehicle of claim 1 wherein the frame comprises: anupper portion having a control module; and a lower portion including adrive mechanism, a front portion, and the rear portion at which theoperator is positioned to access the control module, wherein in thesecond position, the platform is maintained closely adjacent to the rearportion to enable walk-behind use of the vehicle with unobstructedaccess to the control module.
 7. The vehicle of claim 1 wherein theplatform includes an inner end connected to the at least one supportelement and an outer end opposite the inner end, wherein the outer endof the platform includes at least one of a wheel or a roller and thestop mechanism is separate and independent of the respective wheel orroller of the platform and the stop mechanism acts exclusively to limitthe downward pivotal movement of the platform.
 8. The vehicle of claim 1wherein the platform includes an inner end connected to the at least onesupport element and an outer end opposite the inner end, wherein theouter end of the platform is configured without a ground-engagingstructure and wherein the one-handed manipulation is performed on theouter end of the platform.
 9. The vehicle of claim 1 wherein upondisengagement of the latch mechanism relative to the rear portion of thevehicle frame, the platform pivotally moves from the generally upright,second position into the generally horizontal first position via theaction of gravitational forces, and wherein the stop mechanism ispositioned to cause releasable engagement of the at least one supportelement against the stop mechanism via gravitational forces.
 10. Thevehicle of claim 1 wherein the pivot mechanism includes a first pivotpoint and a second pivot point with the respective first and secondpivot points disposed on opposite sides of the platform, and wherein thelatch mechanism is disposed on at least one of the opposite sides of theplatform.
 11. The vehicle of claim 1, comprising: a mounting framesecured to the rear portion of the vehicle frame when the latchingmechanism is releasably engaged and disengaged, respectively, to themounting frame to releasably secure and release, respectively, theplatform in the respective first and second positions relative to therear portion of the vehicle frame.
 12. The vehicle of claim 1 whereinthe stop mechanism is spaced apart from the pivot mechanism.
 13. Thevehicle of claim 1 wherein the at least one support element isindependent of the stop mechanism and freely movable relative to stopmechanism when disengaged relative to the stop mechanism.
 14. Aself-propelled vehicle comprising: a frame; a platform including aninner end pivotally mounted, via pivot mechanism, relative to a rearportion of the vehicle frame, the platform being pivotally movablebetween a first position in which the platform extends in a generallyhorizontally orientation from the rear portion of the frame and isspaced above a ground surface to support a rider standing in an elevatedposition during ride-on operation of the vehicle and a second positionin which the platform is removably secured in a generally uprightposition adjacent the rear portion of the frame to enable walk-behindoperation of the vehicle, wherein the pivot mechanism is disposed oneach of opposite sides of the platform and comprises a pivot pin andwherein the pivot mechanism also comprises the inner end of the platformincluding a first slot slidably movable along and rotatable about thepivot pin; a stop mechanism mounted at the rear portion of the vehicleadjacent to the pivot mechanism, the stop mechanism configured to engagethe inner end of the platform to prevent pivotal movement of theplatform downward beyond the generally horizontal orientation of thefirst position of the platform, wherein the stop mechanism isindependent and separate from the platform, and wherein the stopmechanism is separate from, and independent of, the pivot mechanism; anda latch mechanism disposed on at least one of the opposite sides of theplatform at the inner end of the platform, and configured to be engagedto releasably secure the platform relative to the rear portion of theframe when the platform is in the second position and to be disengagedrelative to the rear portion of the frame when the platform is in thefirst position.
 15. The vehicle of claim 14, wherein the latch mechanismcomprises: a second slot spaced laterally rearward from the pivot pin;and a securing pin disposed on the inner end of the platform in alocation to be external to the second slot when the platform is in thefirst position and to be slidably inserted into the second slot when theplatform is in the second position.
 16. A self-propelled vehiclecomprising: a frame; a platform including an inner portion pivotallymounted, via a pivot mechanism, relative to a rear portion of thevehicle frame, the platform being pivotally movable between a firstposition in which the platform extends in a generally horizontallyorientation from the rear portion of the frame and is spaced above aground surface to support a rider standing in an elevated positionduring ride-on operation of the vehicle and a second position in whichthe platform is removably secured in a generally upright positionadjacent the rear portion of the frame to enable walk-behind operationof the vehicle; a stop mechanism mounted at the rear portion of thevehicle adjacent to the pivot mechanism, the stop mechanism configuredto releasably engage the inner portion of the platform to preventpivotal movement of the platform downward beyond the generallyhorizontal orientation of the first position of the platform, whereinthe stop mechanism is independent and separate from the platform andwherein the stop mechanism is separate and independent of the pivotmechanism; at least one mounting member including: a first portionmountable to an end surface of the rear portion of the vehicle frame andextending generally parallel to the end surface; and a second portionextending outwardly from the first portion of the mounting member, in aplane generally perpendicular to the first portion of the mountingmember, to enable the pivotal mounting of the inner portion of theplatform at a point spaced from, but adjacent to the end surface.
 17. Aself-propelled vehicle comprising: a frame; a platform including aninner portion pivotally mounted, via a pivot mechanism, relative to arear portion of the vehicle frame, wherein the platform is pivotallymovable between a first position in which the platform extends in agenerally horizontally orientation from the rear portion of the frameand is spaced above a ground surface to support a rider standing in anelevated position during ride-on operation of the vehicle and a secondposition in which the platform is removably secured in a generallyupright position adjacent the rear portion of the frame to enablewalk-behind operation of the vehicle; a stop mechanism mounted at therear portion of the vehicle adjacent to the pivot mechanism, wherein thestop mechanism is configured to releasably engage the inner portion ofthe platform to prevent pivotal movement of the platform downward beyondthe generally horizontal orientation of the first position of theplatform, wherein the stop mechanism is independent and separate fromthe platform, and wherein the stop mechanism is separate and independentof the pivot mechanism; at least one mounting member including: a firstportion mountable to a side surface of the frame of the vehicle andextending generally parallel to the side surface of the frame; and asecond portion extending outwardly and rearwardly from the first portionof the mounting frame, in a plane generally parallel to the firstportion, to enable the pivotal mounting of the inner portion of theplatform at a point spaced from, but adjacent the rear portion of thevehicle frame.
 18. A platform system for a self-propelled vehicle, theplatform system comprising: a platform including a surface sized andshaped to define an operator zone, the platform comprising an innerportion and an outer portion; a pivoting mechanism configured forpivotally mounting the inner portion of the platform relative to a rearportion of the self-propelled vehicle to enable movement of the outerportion between a releasably securable, generally upright storageposition adjacent the rear portion of the self-propelled vehicle and agenerally horizontal in-use position extending outwardly away from therear portion of the vehicle to locate the operator zone adjacent acontrol mechanism of the self-propelled vehicle; a limiting mechanismconfigured to be secured relative to the rear portion of theself-propelled vehicle and configured to prevent pivotal movement of theouter portion of the platform downward below the generally horizontalin-use position, wherein the limiting mechanism is independent of, andseparate from, the platform, and wherein the limiting mechanism isindependent of, and separate from, the pivot mechanism; and a latchmechanism at least partially disposed on the inner portion of theplatform and configured to be automatically releasably engaged relativeto the rear portion of the vehicle frame via one-handed manipulation ofthe outer portion of the platform to releasably secure the platform inthe generally upright storage position and configured to beautomatically disengaged relative to the rear portion of the vehicleframe via one-handed manipulation of the outer portion of the platformto release the platform from the upright storage position for movementinto the in-use position.
 19. The platform system of claim 18 whereinthe limiting mechanism is spaced apart from the pivot mechanism andwherein the pivoting mechanism comprises: a mounting frame securableonto the rear portion of the self-propelled vehicle; a first portiondisposed on the mounting frame to enable pivotal mounting of theplatform relative to the rear portion of the self-propelled vehicle; anda second portion disposed on the platform to enable releasable securingof the platform in the upright storage position.
 20. A platform systemcomprising: a platform including a surface sized and shaped to define anoperator zone; a positioning mechanism configured to pivotally mount theplatform relative to a rear portion of a self-propelled vehicle suchthat the platform is movable between a releasably securable, generallyupright storage position adjacent the rear portion of the vehicle and agenerally horizontal in-use position extending outwardly and rearwardlyaway from the rear portion of the vehicle to locate the operator zoneadjacent a control mechanism of the self-propelled vehicle, wherein thepositioning mechanism comprises: a mounting frame securable onto therear portion of the self-propelled vehicle; a first portion disposed onthe mounting frame to enable the pivotal mounting of the platformrelative to the rear portion of the self-propelled vehicle; a secondportion disposed on the platform to enable the releasable securing ofthe platform in the storage position; and a first reciprocating portiondisposed on at least one of the mounting frame or the platform, thefirst reciprocating portion sized and positioned to releasably engagethe second portion when the platform is in the upright storage position;and a limiting mechanism configured to be secured in a fixed positionrelative to the rear portion of the self-propelled vehicle andconfigured to prevent pivotal movement of the platform downward belowthe generally horizontal in-use position, wherein the limiting mechanismis independent of, and separate from, the platform and wherein thelimiting mechanism is independent of, and separate from, the positioningmechanism.
 21. The platform system of claim 20 wherein the secondportion comprises a hook member rotatably mounted to the platform withthe hook member including a first slot, and wherein the firstreciprocating portion is mounted on the mounting frame and comprises asecond pin configured to releasably receive the first slot of the hookmember.
 22. The platform system of claim 20 wherein the first portioncomprises: a first pin and a second, closed elongate slot defined in asupport arm of the platform in which the first pin is pivotally andslidably movable, wherein the second portion comprises a third pin, andwherein the first reciprocating portion is disposed on the mountingframe and comprises a third open slot configured to slidably receive thethird pin.
 23. The vehicle of claim 20 wherein when the platform is inthe generally upright storage position, the platform extends generallyparallel to an end surface of the rear portion of the vehicle frame. 24.A self-propelled vehicle comprising: a frame; and a platform pivotallymounted, via a pivot pin, to a rear portion of the vehicle frame andpivotally movable between a first position in which the platform extendsgenerally horizontally from the rear portion of the frame to support arider during operation of the vehicle and a second position in which theplatform is removably secured in a generally upright position adjacentthe rear portion of the frame to enable walk-behind operation of thevehicle, wherein the platform comprises a support arm including a firstportion positioned underneath the platform and a second portion forminga generally obtuse angle relative to the first portion, the secondportion extending away from the platform inwardly toward the frame ofthe vehicle for pivotal mounting to the pivot pin, wherein the secondportion of the support arm rests on top of the stop mechanism when theplatform is in the first position.
 25. A self-propelled vehiclecomprising: a frame including a rear portion; a platform pivotallymounted, via a pivot mechanism, to the rear portion of the vehicle framewherein the pivot mechanism includes a pivot pin located adjacent to therear portion of the frame on each of opposite sides of the platform,wherein the platform is pivotally movable between a first position inwhich the platform extends generally horizontally from the rear portionof the frame to support a rider during operation of the vehicle and asecond position in which the platform is removably secured in agenerally upright position adjacent the rear portion of the frame toenable walk-behind operation of the vehicle; a latch mechanism disposedon at least one of the opposite sides of the platform, and configured tobe engaged to releasably secure the platform relative to the rearportion of the frame when the platform is in the second position and tobe disengaged relative to the rear portion of the frame when theplatform is in the first position, wherein the pivot mechanism includesa stop mechanism positioned adjacent to, and spaced from, the pivot pinto limit downward pivoting movement of the platform relative to theframe when the platform is in the first position, and wherein the stopmechanism is a generally rectangular-shaped block rotatably positionableinto at least two positions, in which each position causes a differentsurface of the block to support the pivot arm, and each differentsurface being at a different angle relative to the frame, to cause thesupport to be at a different height relative to the frame to therebyposition the operator on the platform at different heights relative tothe frame.
 26. A method of supporting a rider behind a self-propelledloader, the method comprising: mounting, via a pivot mechanism, at leastone support arm of a platform relative to a rear portion of theself-propelled loader to enable positioning the platform in a generallyupright storage position to operate the loader in a walk-behind mode orpositioning the platform in a generally horizontal position to operatethe loader in a ride-on mode in which a user stands on the platformbehind the loader; providing the walk-behind mode of operation of theloader via releasably securing the platform in the generally uprightposition adjacent to, and relative to, the rear portion of the loadervia a hands-free releasable engagement of a latch mechanism relative tothe rear portion of the loader, and including arranging the latchmechanism to be located on at least one of the rear portion of theloader and the at least one support arm; providing the ride-on mode ofoperation of the loader, when the latch mechanism is disengaged, viapreventing downward pivotal movement of the platform beyond thegenerally horizontal position by releasably engaging the at least onesupport arm of the platform via a stop mechanism, and includingarranging the stop mechanism to be located at the rear portion of theloader and wherein the stop mechanism is separate from, and independentof, the pivot mechanism; and switching between the walk-behind mode andthe ride-on mode via selectively pivotally moving the platform, via asingle-handed manipulation of an outer end of the platform, between thereleasably securable generally upright position and the generallyhorizontal position.
 27. The method of claim 26 wherein arranging thelatch mechanism to be located on the rear portion of the loadercomprises: providing the latch mechanism on a mounting frame interposedbetween the rear portion of the loader and the at least one support arm.28. The method of claim 26 wherein arranging the stop mechanism to belocated at the rear portion of the loader comprises: positioning thestop mechanism, on a mounting frame attached to the rear portion of theloader, to releasably engage an inner portion of the at least onesupport arm.
 29. The method of claim 26 wherein providing the ride-onmode of operation of the loader comprises: arranging the stop mechanismto be spaced apart from the pivot mechanism.
 30. The method of claim 26wherein switching between the walk-behind mode and the ride-on mode viathe single-handed manipulation comprises: additionally using a secondhand, at the same time as the single hand, to perform the manipulationof the outer end of the platform.